Also used as "meshk" for short.
"Today inbetween classes, I was walking down the crowded stairwell when all the sudden traffic stopped. 4 meshkys decided to stop for a small chit chat and a small step dance"
It's generally used in two main contexts; either to describe jet black garments/objects or as an adjective/noun for people with very dark black HAIR, EYEBROWS or EYES, in a completely NON-derogatory manner!
It is never used by the general Persian speaker to describe people with darker skin colour e.g. those of African descent, let alone in a derogatory way (as opposed to what's been suggested here before).
Helena: no, meshky!